Abstract: This Tractor power shift gearbox off running-in test bench is developed for a well-known transmission parts manufacturer abroad,specially used for the downline detection of power shift tractor gearbox.The research and development is based on the functional characteristics of the power shift tractor gearbox and the demand of the factory production line assembly process.The test bench is equipped with clamping device,driving device,loading device,detection device,hydraulic system and its energy feedback system,and developed a special electronic control unit and data measurement and acquisition system.The actual use of the equipment shows that:workpiece clamping is convenient and fast,meet the requirements of the rhythm;The closed-loop feedback of energy is realized,and the energy saving rate is as high as 70% under loading running-in condition.The detection system has full functions,which can detect 28 signals including torque,speed,temperature,pressure,noise and flow.The test bench has been put into production and used for more than one year,during which it has been running smoothly.It can be used for testing of various types of gearbox.It is convenient to operate,safe and reliable.